Main Title |
Kinetics and Mechanism of Precipitation and Nature of the Precipitatie Obtained in Phosphate Removal from Waste Water Using Aluminum (III) and Iron (III) Salts. |
Author |
Rech, Howard L. ;
Ghassem, Masood ;
|
CORP Author |
Atomics International, Canoga Park, Calif. |
Year Published |
1970 |
Report Number |
FWQA-14-12-158; FWQA-17010-EKI; 03457,; 17010-EKI-04/70 |
Stock Number |
PB-196 737 |
Additional Subjects |
( Water pollution ;
Phosphates) ;
( Sewage treatment ;
Phosphates) ;
( Precipitation(Chemistry) ;
Phosphorus inorganic acids) ;
( Aluminum ;
Sewage treatment) ;
Iron ;
Evaluation ;
pH ;
Settling ;
Solubility ;
Precipitates ;
Turbidity ;
Nutrients ;
Chemical removal(Sewage treatment) ;
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB-196 737 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
87p |
Abstract |
An investigation was conducted of the rate, mechanism and stoichiometry of phosphate precipitation with aluminum and ferric salts from pure phosphate solutions and secondary effluent. These studies showed that the reactions of orthophosphate ion with both Al(III) and Fe(III) are completed in less than 1 second. The effects of pH, reactant concentration, and reagent aging on the efficiency of phosphate removal were evaluated in batch precipitation experiments. The pH of optimum orthophosphate precipitation was found to be close to 6.0 for Al(III) and in the vicinity of 3.5 to 4.0 for Fe(III). At constant pH, with both Fe(III) and Al(III) up to about a 1:1 molar ratio, orthophosphate removal was directly proportional to amount of added cation, indicating occurrence of a chemical reaction. Dilute solutions of Fe(III) were found to undergo extensive hydrolysis on aging with a resultant loss of capacity to precipitate phosphate. The removal of condensed phosphates by precipitation with aluminum and iron salts was found to be strongly dependent on pH and the reactant concentration ratio. Precipitates obtained in the reaction of orthophosphate with aluminum and ferric salts were examined by X-ray diffraction analysis after drying and heating to 104C and to 600C. Both precipitates remained amorphous, except that ferric phosphate was identified after ignition at 600C. (WRSIC abstract) |
Supplementary Notes |
Paper copy available from Superintendent of Documents, GPO, Washington, D. C. 20402. $0.75 as I67.13/4:17010-EKI-04/70. |
NTIS Title Notes |
Water pollution control research series. |
PUB Date Free Form |
Apr 70, |
Category Codes |
13B; 68D |
NTIS Prices |
SOD MF A01 |
Document Type |
NT |
Cataloging Source |
NTIS/MT |
Control Number |
326515454 |
Origin |
NTIS |
Type |
CAT |